noun tri·an·gle \ˈtrī-ˌaŋ-gəl\

: a shape that is made up of three lines and three angles

: something that is shaped like a triangle

: a musical instrument that is made of a steel rod bent into the shape of a triangle and that you play by hitting with a metal rod

Full Definition of TRIANGLE

:  a polygon having three sides — compare spherical triangle
a :  a percussion instrument consisting of a rod of steel bent into the form of a triangle open at one angle and sounded by striking with a small metal rod
b :  a drafting instrument consisting of a thin flat right-angled triangle of wood or plastic with acute angles of 45 degrees or of 30 degrees and 60 degrees
:  a situation in which one member of a couple is involved in a love affair with a third person

Examples of TRIANGLE

  1. She cut the sandwiches into triangles.

Illustration of TRIANGLE

Origin of TRIANGLE

Middle English, from Anglo-French, from Latin triangulum, from neuter of triangulus triangular, from tri- + angulus angle
First Known Use: 14th century
TRIANGLES Defined for Kids


noun tri·an·gle \ˈtrī-ˌaŋ-gəl\

Definition of TRIANGLE for Kids

:  a flat geometric figure that has three sides and three angles
:  something that has three sides and three angles <a triangle of land>
:  a musical instrument made of a steel rod bent in the shape of a triangle with one open angle
Medical Dictionary


noun tri·an·gle \ˈtrī-ˌaŋ-gəl\

Medical Definition of TRIANGLE

:  a three-sided region or space and especially an anatomical one—see anterior triangle, posterior triangle, scarpa's triangle, suboccipital triangle, superior carotid triangle
July 29, 2015
indomitable Hear it
incapable of being subdued or conquered
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